/*-
 * ============LICENSE_START=======================================================
 * SDC
 * ================================================================================
 * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ============LICENSE_END=========================================================
 */
package org.openecomp.core.utilities.deserializers;

import com.google.gson.JsonArray;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonPrimitive;
import java.lang.reflect.Type;
import java.util.Objects;
import java.util.Optional;
import org.onap.sdc.tosca.datatypes.model.RequirementDefinition;

public class RequirementDefinitionDeserializer implements JsonDeserializer<RequirementDefinition> {

    static final String CAPABILITY = "capability";
    static final String NODE = "node";
    static final String RELATIONSHIP = "relationship";
    private static final String OCCURRENCES = "occurrences";

    @Override
    public RequirementDefinition deserialize(JsonElement jsonElement, Type type, JsonDeserializationContext jsonDeserializationContext) {
        JsonObject jsonObject = jsonElement.getAsJsonObject();
        RequirementDefinition requirementDefinition = new RequirementDefinition();
        setRequirementValues(jsonObject, requirementDefinition);
        Optional<Object[]> occurrences = handleOccurrences(jsonObject);
        occurrences.ifPresent(requirementDefinition::setOccurrences);
        return requirementDefinition;
    }

    private void setRequirementValues(JsonObject jsonObject, RequirementDefinition requirementDefinition) {
        JsonElement capabilityElement = jsonObject.get(CAPABILITY);
        if (!Objects.isNull(capabilityElement)) {
            requirementDefinition.setCapability(capabilityElement.getAsString());
        }
        JsonElement nodeElement = jsonObject.get(NODE);
        if (!Objects.isNull(nodeElement)) {
            requirementDefinition.setNode(nodeElement.getAsString());
        }
        JsonElement relationshipElement = jsonObject.get(RELATIONSHIP);
        if (!Objects.isNull(relationshipElement)) {
            requirementDefinition.setRelationship(relationshipElement.getAsString());
        }
    }

    private Optional<Object[]> handleOccurrences(JsonObject jsonObject) {
        JsonElement occurrencesElement = jsonObject.get(OCCURRENCES);
        if (Objects.isNull(occurrencesElement)) {
            return Optional.empty();
        }
        JsonArray occurrences = occurrencesElement.getAsJsonArray();
        Object[] fixedOccurrences = new Object[occurrences.size()];
        for (int i = 0; i < occurrences.size(); i++) {
            JsonElement currElement = occurrences.get(i);
            // values inside occurrences array can be either String or Integer
            if (currElement.isJsonPrimitive()) {
                JsonPrimitive jsonPrimitive = currElement.getAsJsonPrimitive();
                if (jsonPrimitive.isNumber()) {
                    fixedOccurrences[i] = jsonPrimitive.getAsNumber().intValue();
                } else {
                    fixedOccurrences[i] = jsonPrimitive.getAsString();
                }
            }
        }
        return Optional.of(fixedOccurrences);
    }
}
